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Author: Frank F. E. Owen
Publisher: McGraw-Hill Companies
Published: 1982
Total Pages: 332
ISBN-13:
DOWNLOAD EBOOKDownload or read book PCM and Digital Transmission Systems written by Frank F. E. Owen and published by McGraw-Hill Companies. This book was released on 1982 with total page 332 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author: Ayman Elmassarawy
Publisher: Ayman Elmassarawy
Published:
Total Pages: 572
ISBN-13:
DOWNLOAD EBOOKDigital transmission systems are the backbone of modern communication networks, enabling the exchange of information across various media, such as copper wires, optical fibers, radio waves, and satellites. These systems use digital signals to encode, transmit, and decode data, such as voice, video, text, and images. Digital transmission systems have many advantages over analog systems, such as higher capacity, better quality, lower cost, and more flexibility. However, designing and implementing digital transmission systems is not a trivial task. It requires a solid understanding of the fundamental principles, techniques, and standards that govern the operation and performance of these systems. It also requires a familiarity with the various technologies and components that are used to realize these systems, such as modulation, multiplexing, coding, switching, amplification, and synchronization. This book aims to provide a comprehensive and up-to-date introduction to the fundamentals of digital transmission systems, covering both theoretical and practical aspects. It is intended for students, engineers, and researchers who want to learn the basics of digital transmission systems, as well as for professionals who want to refresh or update their knowledge in this field. The book is also important for communication engineers and operators who are involved in the planning, design, installation, operation, maintenance, and troubleshooting of digital transmission systems and networks. The book covers the most common and widely used standards and technologies in digital transmission, such as PCM, PDH, SDH, OTN, WDM, ADSL, GPON, and radio waves. The book also provides the latest information on the evolution and trends of digital transmission, such as liquid OTN, fiber-optic transmission systems, and digital transmission networks. The book helps communication engineers and operators to understand the principles, advantages, limitations, and challenges of digital transmission systems and to apply them to their specific needs and scenarios. The book is organized into eight chapters, each covering a major topic in digital transmission systems. The chapters are as follows: Chapter 1 introduces the importance, motivations, and overview of digital transmission systems, and provides a conclusion and some questions for review. Chapter 2 explains the fundamentals of pulse code modulation (PCM), which is the most common technique for converting analog signals into digital signals. It also describes the structure and signaling of the 2 Mbit/s (E1) frame, which is the basic unit of transmission in many digital systems. Chapter 3 discusses the plesiochronous digital hierarchy (PDH), which is a legacy standard for multiplexing and transporting digital signals over copper wires or optical fibers. It also covers the frame structure, synchronization, signaling, error detection and correction, network architecture, and limitations of PDH. Chapter 4 introduces the synchronous digital hierarchy (SDH), which is a more advanced and widely adopted standard for multiplexing and transporting digital signals over optical fibers. It also covers the general and specific frame structures, multiplexing hierarchy, network and management, network protections, and synchronization of SDH. Chapter 5 presents optical fiber technology, which is the main medium for transmitting digital signals over long distances and at high speeds. It also covers the technical overview, physics of light, and design and protection of fiber optic cables. Chapter 6 explores the wavelength division multiplexing (WDM) technology, which is a technique for increasing the capacity and efficiency of optical fiber networks by using multiple wavelengths of light. It also covers the WDM and optical fiber structure, active and passive optical components, optical amplification, noise calculation, fiber-optic transmission systems, and fiber-optic networks. Chapter 7 describes the optical transport network (OTN), which is a standard for multiplexing and transporting various types of digital signals over optical fibers using a common format. It also covers the OTN fundamentals, multiplexing overview, frame structure, evolution to liquid OTN, and important topics in OTN. Chapter 8 reviews the ADSL modems, GPON fundamentals, and radio waves propagations, which are some of the technologies and phenomena that are related to digital transmission systems. The book also includes two appendices that provide some supplementary information on BIP, SDH Synchronization, OTN protection and more. The book assumes that the reader has some basic knowledge of mathematics, physics, and electronics, as well as some familiarity with communication systems and networks. The book provides clear explanations, examples, figures, tables, and equations to illustrate the concepts and methods of digital transmission systems. The book also provides questions at the end of each chapter to test the reader’s understanding and to stimulate further exploration. The book is written by who is a Doctor of Electrical Engineering, Egypt. Ayman Elmassarawy has a PhD in communication systems and has over 20 years of research and practical experience in the field of digital transmission systems in the field of digital transmission systems. The book is a valuable resource for anyone who wants to learn the fundamentals of digital transmission systems and to gain a deeper insight into the current and emerging technologies and standards in this field. The book is also a useful reference for anyone who is involved in the design, implementation, operation, or maintenance of digital transmission systems and networks.
Download or read book Digital Transmission Systems: From PCM to OTN written by Ayman Elmassarawy and published by Ayman Elmassarawy. This book was released on with total page 572 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital transmission systems are the backbone of modern communication networks, enabling the exchange of information across various media, such as copper wires, optical fibers, radio waves, and satellites. These systems use digital signals to encode, transmit, and decode data, such as voice, video, text, and images. Digital transmission systems have many advantages over analog systems, such as higher capacity, better quality, lower cost, and more flexibility. However, designing and implementing digital transmission systems is not a trivial task. It requires a solid understanding of the fundamental principles, techniques, and standards that govern the operation and performance of these systems. It also requires a familiarity with the various technologies and components that are used to realize these systems, such as modulation, multiplexing, coding, switching, amplification, and synchronization. This book aims to provide a comprehensive and up-to-date introduction to the fundamentals of digital transmission systems, covering both theoretical and practical aspects. It is intended for students, engineers, and researchers who want to learn the basics of digital transmission systems, as well as for professionals who want to refresh or update their knowledge in this field. The book is also important for communication engineers and operators who are involved in the planning, design, installation, operation, maintenance, and troubleshooting of digital transmission systems and networks. The book covers the most common and widely used standards and technologies in digital transmission, such as PCM, PDH, SDH, OTN, WDM, ADSL, GPON, and radio waves. The book also provides the latest information on the evolution and trends of digital transmission, such as liquid OTN, fiber-optic transmission systems, and digital transmission networks. The book helps communication engineers and operators to understand the principles, advantages, limitations, and challenges of digital transmission systems and to apply them to their specific needs and scenarios. The book is organized into eight chapters, each covering a major topic in digital transmission systems. The chapters are as follows: Chapter 1 introduces the importance, motivations, and overview of digital transmission systems, and provides a conclusion and some questions for review. Chapter 2 explains the fundamentals of pulse code modulation (PCM), which is the most common technique for converting analog signals into digital signals. It also describes the structure and signaling of the 2 Mbit/s (E1) frame, which is the basic unit of transmission in many digital systems. Chapter 3 discusses the plesiochronous digital hierarchy (PDH), which is a legacy standard for multiplexing and transporting digital signals over copper wires or optical fibers. It also covers the frame structure, synchronization, signaling, error detection and correction, network architecture, and limitations of PDH. Chapter 4 introduces the synchronous digital hierarchy (SDH), which is a more advanced and widely adopted standard for multiplexing and transporting digital signals over optical fibers. It also covers the general and specific frame structures, multiplexing hierarchy, network and management, network protections, and synchronization of SDH. Chapter 5 presents optical fiber technology, which is the main medium for transmitting digital signals over long distances and at high speeds. It also covers the technical overview, physics of light, and design and protection of fiber optic cables. Chapter 6 explores the wavelength division multiplexing (WDM) technology, which is a technique for increasing the capacity and efficiency of optical fiber networks by using multiple wavelengths of light. It also covers the WDM and optical fiber structure, active and passive optical components, optical amplification, noise calculation, fiber-optic transmission systems, and fiber-optic networks. Chapter 7 describes the optical transport network (OTN), which is a standard for multiplexing and transporting various types of digital signals over optical fibers using a common format. It also covers the OTN fundamentals, multiplexing overview, frame structure, evolution to liquid OTN, and important topics in OTN. Chapter 8 reviews the ADSL modems, GPON fundamentals, and radio waves propagations, which are some of the technologies and phenomena that are related to digital transmission systems. The book also includes two appendices that provide some supplementary information on BIP, SDH Synchronization, OTN protection and more. The book assumes that the reader has some basic knowledge of mathematics, physics, and electronics, as well as some familiarity with communication systems and networks. The book provides clear explanations, examples, figures, tables, and equations to illustrate the concepts and methods of digital transmission systems. The book also provides questions at the end of each chapter to test the reader’s understanding and to stimulate further exploration. The book is written by who is a Doctor of Electrical Engineering, Egypt. Ayman Elmassarawy has a PhD in communication systems and has over 20 years of research and practical experience in the field of digital transmission systems in the field of digital transmission systems. The book is a valuable resource for anyone who wants to learn the fundamentals of digital transmission systems and to gain a deeper insight into the current and emerging technologies and standards in this field. The book is also a useful reference for anyone who is involved in the design, implementation, operation, or maintenance of digital transmission systems and networks.
Author: Ayman Elmaasarawy
Publisher: Independently Published
Published: 2021-05-06
Total Pages: 0
ISBN-13:
DOWNLOAD EBOOKDue to the competitions between the telecommunication service providers, the required capacities are increasing all the time. It is important for these providers to develop a network that can transfer more data bytes from one place to another. In addition, the mobile traffic and the internet services need more capacities in the telecommunication networks. Therefore, it is mandatory for the networks to handle large amounts of data in a fast and a reliable way. Of course, one possibility would be Ethernet traffic, but in cellular transmission networks there are a strict requirement for delay, data loss and synchronization and this is why the Ethernet is not yet supported.The Synchronous Digital Hierarchy (SDH) is one answer for increasing the network data traffic. For example, if we need to transfer 63 × 2.048 Mb/s (E1) signals from one place to another a huge amount of wires will be needed, on the other hand the SDH needs only two fibers to do the same operation. Many vendors have a product called STM1 multiplexer and its functionality to add and drop 63 × 2.048 Mbit/s into 155.52 Mbit/s (STM-1). The bit rates of the basic signals in the SDH are derived from the same clock source, which means that the SDH is completely synchronous transmission system. SDH has many different hierarchy levels starting from 155.52 Mbit/s to 10 Gbit/s and the STM-1 with a bit rate of 155.52 Mbit/s is the basic module of the SDH system. The SDH signal is terminated to E1 (2.048 Mbit/s) signals by using terminal multiplexer.Before the SDH multiplexer operates in the telecommunication market, there is a huge amount of work to put the requirements specifications, by studying the reality of the market needs. Many chip manufacturers have SDH chips in their product catalog, so one has to make a decision which manufacturer's chip to use. In addition, one must decide how to handle overhead bytes and how to implement all this in network manager software. After all these decisions, we have a huge amount of data and the last thing to do is to decide which features are implemented and which are not. Because of time-to-market pressures, the implementation has to be phased and the first phase must contain only the necessary functionality and nothing more to reduce the development time to minimum.The Synchronous Digital Hierarchy (SDH) multiplexers form the core part of the backbone telecommunication networks, and the effective design, reliability analysis and training are essential to managing SDH network effectively. Today and shortly, the demands to transfer a tremendous mass of data among the various applications in many fields inside the country become an exclusive responsibility particularly with the significant developments of the clouding policies in the different forms such the data centers and the implementations of many smart applications of the 5G in the various areas of the information technologies. The current design of the core communication network consists of 3 independent zones, the 1'st zone is layer 1 and layer 2 which recognized as the physical layer of the core optical network such Optical Transport Network (OTN), the 2'nd band is layer 3 which viewed as IP core network, and the last zone is the access and the application layers such 4G network. The challenge in the current communication model is no associations among these 3 zones of the communication network to optimize the capacities and the needed resources which are required to carry the data among any of them. Now the optical transport network (OTN) represents the critical point of carrying a tremendous amount of data for the mobile network such 4G between the different sites.
Download or read book Fundamentals of Digital Transmission Systems written by Ayman Elmaasarawy and published by Independently Published. This book was released on 2021-05-06 with total page 0 pages. Available in PDF, EPUB and Kindle. Book excerpt: Due to the competitions between the telecommunication service providers, the required capacities are increasing all the time. It is important for these providers to develop a network that can transfer more data bytes from one place to another. In addition, the mobile traffic and the internet services need more capacities in the telecommunication networks. Therefore, it is mandatory for the networks to handle large amounts of data in a fast and a reliable way. Of course, one possibility would be Ethernet traffic, but in cellular transmission networks there are a strict requirement for delay, data loss and synchronization and this is why the Ethernet is not yet supported.The Synchronous Digital Hierarchy (SDH) is one answer for increasing the network data traffic. For example, if we need to transfer 63 × 2.048 Mb/s (E1) signals from one place to another a huge amount of wires will be needed, on the other hand the SDH needs only two fibers to do the same operation. Many vendors have a product called STM1 multiplexer and its functionality to add and drop 63 × 2.048 Mbit/s into 155.52 Mbit/s (STM-1). The bit rates of the basic signals in the SDH are derived from the same clock source, which means that the SDH is completely synchronous transmission system. SDH has many different hierarchy levels starting from 155.52 Mbit/s to 10 Gbit/s and the STM-1 with a bit rate of 155.52 Mbit/s is the basic module of the SDH system. The SDH signal is terminated to E1 (2.048 Mbit/s) signals by using terminal multiplexer.Before the SDH multiplexer operates in the telecommunication market, there is a huge amount of work to put the requirements specifications, by studying the reality of the market needs. Many chip manufacturers have SDH chips in their product catalog, so one has to make a decision which manufacturer's chip to use. In addition, one must decide how to handle overhead bytes and how to implement all this in network manager software. After all these decisions, we have a huge amount of data and the last thing to do is to decide which features are implemented and which are not. Because of time-to-market pressures, the implementation has to be phased and the first phase must contain only the necessary functionality and nothing more to reduce the development time to minimum.The Synchronous Digital Hierarchy (SDH) multiplexers form the core part of the backbone telecommunication networks, and the effective design, reliability analysis and training are essential to managing SDH network effectively. Today and shortly, the demands to transfer a tremendous mass of data among the various applications in many fields inside the country become an exclusive responsibility particularly with the significant developments of the clouding policies in the different forms such the data centers and the implementations of many smart applications of the 5G in the various areas of the information technologies. The current design of the core communication network consists of 3 independent zones, the 1'st zone is layer 1 and layer 2 which recognized as the physical layer of the core optical network such Optical Transport Network (OTN), the 2'nd band is layer 3 which viewed as IP core network, and the last zone is the access and the application layers such 4G network. The challenge in the current communication model is no associations among these 3 zones of the communication network to optimize the capacities and the needed resources which are required to carry the data among any of them. Now the optical transport network (OTN) represents the critical point of carrying a tremendous amount of data for the mobile network such 4G between the different sites.
Author: David R. Smith
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 822
ISBN-13: 1441989331
DOWNLOAD EBOOKDigital Transmission Systems, Third Edition, is a comprehensive overview of the theory and practices of digital transmission systems used in digital communication. This new edition has been completely updated to include the latest technologies and newest techniques in the transmission of digitized information as well as coverage of digital transmission design, implementation and testing.
Download or read book Digital Transmission Systems written by David R. Smith and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 822 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital Transmission Systems, Third Edition, is a comprehensive overview of the theory and practices of digital transmission systems used in digital communication. This new edition has been completely updated to include the latest technologies and newest techniques in the transmission of digitized information as well as coverage of digital transmission design, implementation and testing.
Author: David R. Smith
Publisher: Springer Science & Business Media
Published: 2013-11-11
Total Pages: 580
ISBN-13: 1475711859
DOWNLOAD EBOOKIn the development of telecommunication networks throughout the world, digital transmission has now replaced analog transmission as the predominant choice for new transmission facilities. This trend began in the early 1960s when the American Telephone and Telegraph Company first introduced pulse code modulation as a means of increasing capacity in their cable plant. Since that time, digital transmission applications have grown dramatically, notably in the United States, Canada, Japan, and Western Europe. With the rapidity of digital transmission developments and imple mentation, however, there has been a surprising lack of textbooks written on the subject. This book grew out of my work, research, and teaching in digital transmission systems. My objective is to provide an overview of the subject. To accomplish this end, theory has been blended with practice in order to illustrate how one applies theoretical principles to actual design and imple mentation. The book has abundant design examples and references to actual systems. These examples have been drawn from common carriers, manufac turers, and my own experience. Considerable effort has been made to include up-to-date standards, such as those published by the CCITT and CCIR, and to interpret their recommendations in the context of present-day digital transmission systems.
Download or read book Digital Transmission Systems written by David R. Smith and published by Springer Science & Business Media. This book was released on 2013-11-11 with total page 580 pages. Available in PDF, EPUB and Kindle. Book excerpt: In the development of telecommunication networks throughout the world, digital transmission has now replaced analog transmission as the predominant choice for new transmission facilities. This trend began in the early 1960s when the American Telephone and Telegraph Company first introduced pulse code modulation as a means of increasing capacity in their cable plant. Since that time, digital transmission applications have grown dramatically, notably in the United States, Canada, Japan, and Western Europe. With the rapidity of digital transmission developments and imple mentation, however, there has been a surprising lack of textbooks written on the subject. This book grew out of my work, research, and teaching in digital transmission systems. My objective is to provide an overview of the subject. To accomplish this end, theory has been blended with practice in order to illustrate how one applies theoretical principles to actual design and imple mentation. The book has abundant design examples and references to actual systems. These examples have been drawn from common carriers, manufac turers, and my own experience. Considerable effort has been made to include up-to-date standards, such as those published by the CCITT and CCIR, and to interpret their recommendations in the context of present-day digital transmission systems.
Author: David R. Smith
Publisher: Springer Science & Business Media
Published: 2003-11-30
Total Pages: 842
ISBN-13: 9781402075872
DOWNLOAD EBOOKDigital Transmission Systems, Third Edition, is a comprehensive overview of the theory and practices of digital transmission systems used in digital communication. This new edition has been completely updated to include the latest technologies and newest techniques in the transmission of digitized information as well as coverage of digital transmission design, implementation and testing.
Download or read book Digital Transmission Systems written by David R. Smith and published by Springer Science & Business Media. This book was released on 2003-11-30 with total page 842 pages. Available in PDF, EPUB and Kindle. Book excerpt: Digital Transmission Systems, Third Edition, is a comprehensive overview of the theory and practices of digital transmission systems used in digital communication. This new edition has been completely updated to include the latest technologies and newest techniques in the transmission of digitized information as well as coverage of digital transmission design, implementation and testing.
Download or read book Digital Transmission Systems written by P. Bylanski and published by . This book was released on 1980 with total page 456 pages. Available in PDF, EPUB and Kindle. Book excerpt:
Author: Apurba Das
Publisher: Springer Science & Business Media
Published: 2010-08-02
Total Pages: 253
ISBN-13: 3642127436
DOWNLOAD EBOOK"Digital Communications" presents the theory and application of the philosophy of Digital Communication systems in a unique but lucid form. The book inserts equal importance to the theory and application aspect of the subject whereby the authors selected a wide class of problems. The Salient features of the book are: 1. The foundation of Fourier series, Transform and wavelets are introduces in a unique way but in lucid language. 2. The application area is rich and resemblance to the present trend of research, as we are attached with those areas professionally. 3. Elegant exercise section is designed in such a way that, the readers can get the flavor of the subject and get attracted towards the future scopes of the subject. 4. Unparallel tabular, flow chart based and pictorial methodology description will be there for sustained impression of the proposed design/algorithms in mind.
Download or read book Digital Communication written by Apurba Das and published by Springer Science & Business Media. This book was released on 2010-08-02 with total page 253 pages. Available in PDF, EPUB and Kindle. Book excerpt: "Digital Communications" presents the theory and application of the philosophy of Digital Communication systems in a unique but lucid form. The book inserts equal importance to the theory and application aspect of the subject whereby the authors selected a wide class of problems. The Salient features of the book are: 1. The foundation of Fourier series, Transform and wavelets are introduces in a unique way but in lucid language. 2. The application area is rich and resemblance to the present trend of research, as we are attached with those areas professionally. 3. Elegant exercise section is designed in such a way that, the readers can get the flavor of the subject and get attracted towards the future scopes of the subject. 4. Unparallel tabular, flow chart based and pictorial methodology description will be there for sustained impression of the proposed design/algorithms in mind.
Author: Edward A. Lee
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 727
ISBN-13: 9400913036
DOWNLOAD EBOOKThis book concerns digital communication. Specifically, we treat the transport of bit streams from one geographical location to another over various physical media, such as wire pairs, coaxial cable, optical fiber, and radio waves. Further, we cover the mul tiplexing, multiple access, and synchronization issues relevant to constructing com munication networks that simultaneously transport bit streams from many users. The material in this book is thus directly relevant to the design of a multitude of digital communication systems, including for example local and metropolitan area data net works, voice and video telephony systems, the integrated services digital network (ISDN), computer communication systems, voiceband data modems, and satellite communication systems. We extract the common principles underlying these and other applications and present them in a unified framework. This book is intended for designers and would-be designers of digital communication systems. To limit the scope to manageable proportions we have had to be selective in the topics covered and in the depth of coverage. In the case of advanced information, coding, and detection theory, for example, we have not tried to duplicate the in-depth coverage of many advanced textbooks, but rather have tried to cover those aspects directly relevant to the design of digital communication systems.
Download or read book Digital Communication written by Edward A. Lee and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 727 pages. Available in PDF, EPUB and Kindle. Book excerpt: This book concerns digital communication. Specifically, we treat the transport of bit streams from one geographical location to another over various physical media, such as wire pairs, coaxial cable, optical fiber, and radio waves. Further, we cover the mul tiplexing, multiple access, and synchronization issues relevant to constructing com munication networks that simultaneously transport bit streams from many users. The material in this book is thus directly relevant to the design of a multitude of digital communication systems, including for example local and metropolitan area data net works, voice and video telephony systems, the integrated services digital network (ISDN), computer communication systems, voiceband data modems, and satellite communication systems. We extract the common principles underlying these and other applications and present them in a unified framework. This book is intended for designers and would-be designers of digital communication systems. To limit the scope to manageable proportions we have had to be selective in the topics covered and in the depth of coverage. In the case of advanced information, coding, and detection theory, for example, we have not tried to duplicate the in-depth coverage of many advanced textbooks, but rather have tried to cover those aspects directly relevant to the design of digital communication systems.
Author: Bernhard E. Keiser
Publisher: Springer Science & Business Media
Published: 2012-12-06
Total Pages: 466
ISBN-13: 9401571775
DOWNLOAD EBOOKWhat is "digital telephony"? To the authors, the term digital telephony de notes the technology used to provide a completely digital point-to-point voice communication system from end to end. This implies the use of digital technol ogy from one end instrument through the transmission facilities and switching centers to another end instrument. Digital telephony has become possible only because of the recent and ongoing surge of semiconductor developments allowing microminiaturization and high reliability along with reduced costs. This book deals with both the future and the present. Thus, the first chapter is entitled, "A Network in Transition." As baselines, Chapters 2, 3, and 10 provide the reader with the present status of telephone technology in terms of voice digitization as well as switching principles. The book is an outgrowth of the authors' continuing engineering education course, "Digital Telephony," which they have taught since January, 1980, to attendees from business, industry, government, common carriers, and tele phony equipment manufacturers. These attendees come from a wide variety of educational backgrounds. but generally have the equivalent of at least a bachelor's degree in electrical engineering. The book has been written to provide both the engineering student and the practicing engineer a working knowledge of the principles of present and future voice communication systems based upon the use of the public switched network. Problems or discussion questions have been included at the ends of the chapters to facilitate the book's use as a senior level or first year graduate level course text.
Download or read book Digital Telephony and Network Integration written by Bernhard E. Keiser and published by Springer Science & Business Media. This book was released on 2012-12-06 with total page 466 pages. Available in PDF, EPUB and Kindle. Book excerpt: What is "digital telephony"? To the authors, the term digital telephony de notes the technology used to provide a completely digital point-to-point voice communication system from end to end. This implies the use of digital technol ogy from one end instrument through the transmission facilities and switching centers to another end instrument. Digital telephony has become possible only because of the recent and ongoing surge of semiconductor developments allowing microminiaturization and high reliability along with reduced costs. This book deals with both the future and the present. Thus, the first chapter is entitled, "A Network in Transition." As baselines, Chapters 2, 3, and 10 provide the reader with the present status of telephone technology in terms of voice digitization as well as switching principles. The book is an outgrowth of the authors' continuing engineering education course, "Digital Telephony," which they have taught since January, 1980, to attendees from business, industry, government, common carriers, and tele phony equipment manufacturers. These attendees come from a wide variety of educational backgrounds. but generally have the equivalent of at least a bachelor's degree in electrical engineering. The book has been written to provide both the engineering student and the practicing engineer a working knowledge of the principles of present and future voice communication systems based upon the use of the public switched network. Problems or discussion questions have been included at the ends of the chapters to facilitate the book's use as a senior level or first year graduate level course text.
